вот
1) 5x*(12x+7)-4x*(15x-11) = 10+29x60x²+35x-60x²+44x-29x = 1050x = 10|:50x = 0,2
2) (2x-3)²-(2x+1)*(2x-5)=3x-144x²-12x+9-(4x²-10x+2x-5)-3x = -144x²-15x+9-4x²+8x+5 = -14-7x = -14-9-5-7x = -28|:(-7)x = 4
вот
1) 5x*(12x+7)-4x*(15x-11) = 10+29x
60x²+35x-60x²+44x-29x = 10
50x = 10|:50
x = 0,2
2) (2x-3)²-(2x+1)*(2x-5)=3x-14
4x²-12x+9-(4x²-10x+2x-5)-3x = -14
4x²-15x+9-4x²+8x+5 = -14
-7x = -14-9-5
-7x = -28|:(-7)
x = 4